Grinding machine



June 10 1924.

T. S. CRAMPTON GRINDTNG MACHINE 2 Sheets-Sheet. 1

lll l llillllllllllH Filed May a. 1922 June 10, 1924.

Y 1,496,842 T. s. CRAMPTON GRINDTNG MACHINE Filed May 8, 1922 2 Sheets-Sheet 2 Patented June 10, 1924.

THOMAS S. CRAMPTO'N, OF STEMMERSRUN, MARYLAND.

GRINDING MACHINE.

Application filed May 8,

To all whom it may concern:

Be it known that I, THOMAS S. CRAMP- TON, a citizen of the United States, residing at Stemmersrun, in the county of Baltimore and State of Maryland, have invented a new and useful Grinding Machine, of which the following is a specification.

This invention relates to a machine designed for grinding and sharpening tools, polishingutensils, and for like purposes,

one of the objects of the invention being to provide asimple, durable and inexpensive structure which can be operated readily either by hand power or foot power, there being a ratchet mechanism of novel form for converting oscillating or reciprocating motion into rotary motion to drive the mechanism.

With the foregoing and other objects in view which will appear as the description proceeds, the invention resides in the combi nation and arrangement of parts and in the details of construction hereinafter described and claimed, it being understood that, within the scope of what is claimed, changes in the precise embodiment of the invention shown can be made without departing from the spirit of the invention.

In the accompanying drawings the pre ferred form of the invention has been shown.

In said drawings Figure 1 is a front elevation of the device.

Figure 2 is a side elevation.

Figure 3 is a plan view showing a modi fied means for attaching the device to a wall or similar support.

Figure 4 is a section on line 44, Figure 1.

Figure 5 is a section on line 55, F igure 4.

Figure 6 is an enlarged section on line 66, Figure 4.

Referring to the figures by characters of reference 1 designates a casting constituting the body of the machine and provided at its upper end with a bearing 2 in which is journaled a shaft 3 to the end portions of which may be secured grinding and polishing wheels 4. These wheels may be of any kind desired and can be secured to the shaft by any suitable means provided for that purpose. A gear 5 is secured to the shaft 8 and receives motion through a large gear 6 from a shaft 7 journaled in a bearing 8 formed with and extendingtransversely of the casting or body 1. This shaft has an 1922. Serial No. 559,349.

enlarged portion 9 bearing against one side a of the body 1 and extending from this enlarged portion is the squared end 10 of the shaft. This squared portion extends through a ratchet wheel 11 which obviously rotates with the shaft. A coiled spring 12 is secured at one end to the enlarged portion 9 of the shaft 7 and at its other end to the inner face of a drum 13 the internal diameter of which is greater than the diameter of the ratchet 11, the spring 12 serving ,i

to hold the drum normally concentric'with the axle. The drum' might be termed a floating drum because it is movable bodily alonglines extending transversely in any direction through the shaft 7. The drum has an intermediate annular flange 14, the inner end'of the drum being closed by the body 1 while the outer end is closed by a disk 15 detachably secured to the shaft. A coiled spring 16 is extended around the drum at the inner end thereof and is fastened at one end to the drum while its other end is secured to a pin 17 extending laterally from the body'l and provided with an eye 18. The flange 14 and the disk 15 cooperate with the drum 18 to provide a spool on which a flexible actuating element 19 may be wrapped, this element being extended through the eye 18 Formed within the drum 13 are ratchet teeth 20 but these teeth are held normally out of engagement with the rachet 11 because of the supporting action of the spring 12.

The lower portion of the body 1 has a'stationary jaw 21. with which cooperates a clamping member 22 carried by an adjust ing screw 23 extending through an ear 24 on the body. Thus by inserting the edge of a table T or the like between jaw 21 and plate 22 the machine can be fastened in place securely.

The squared end 10 of the shaft 7 is detachably engaged by a crank arm 25 whereby the shaft can be rotated by hand in which event the ratchet Wheel 11, rotating in the direction indicated by the arrow in Figure 5, will rotate independently of the ratchet teeth 20 and the drum 13. Thus motion will be transmitted through gears 6 and 5 to the grinding or polishing wheels. When de sired, however, the crank arm can be removed and by pulling intermittently on the connection 19, by means of a foot pedal or the like a rotation of the parts will be set up. This is caused by the fact that the initial force exerted by each pull will result (4b of the centering spring 19,.

one or more ofthe teeth 20 will en e the ratchet l1 and shaft 7 will be rotated the remainder of the pull exerted. This rotation will place the outer spring 16 under tension and as soon as the connection 19 is released the drum will be recentered by spring 12 and rotated back to its normal position by spring 16.

Instead of mounting the body on a table in the manner described, attaching brackets 26 can be secured to studs 27 outstanding from the body and these brackets can be attached to a wall or the like. They have been illustrated in Figure 3.

For supporting the work being acted on by the wheels et a supporting bar or arm 28 can be extenned from the body 1 and on this bar or arm may be adjustably mounted a rest bar 29.

What is claimed is: v

1. In a machine of the class described the combination with a body, and separate shafts journaled therein, of means for rotating one shaft, said means including a ratchet wheel secured to the shaft, a floating drum yieldingly spaced from the ratchet wheel and having interior ratchet teeth, a spring for holding the drum normally in a predetermined position relative to the body, pull receiving means for shifting the drum to bring its ratchet teeth into engagement with the ratchet wheel and rotate the shaft, and means for transmitting motion between the shafts.

2. A grinding machine of the class described including a drive shaft, a driven shaft, means for transmitting motion be- Consequently I 2: du ring naeaeae tween the shafts, a ratchet wheel. fired upon the drive shaft, a yieldingly centered floating drum extending around the drive shaft, internal ratchet teeth therein normally spaced from the ratchet wheel, a flexible actuating element normally wound upon the drum for shifting the drum to couple it to the ratchet wheel and rotate the drive shaft, and spring means for automatically returning the drive shaft to its initial. position when the drum is uncoupled from the shaft.

3. In a grinding machine of the class de scribed an actuating mechanism including a drive shaft, a ratchet wheel fixed thereon, a floating drum, yielding means for holding the drum normally concentric with the shaft, teeth within the drum normally spaced from the ratchet wheel, and a flexible operating element for shifting the drum relative to the shaft to couple its teeth to the ratchet wheel and then rotate the drum and shaft,

4C. In a grinding machine of the class described an actuating mechanism including a drive shaft, a ratchet wheel fixed thereon, a floating drum, yielding means for holding the drum normally concentric with the shaft, teeth within the drum normally spaced from the ratchet wheel, a flexible operating element for shifting the drum relative to the shaft to couple its teeth to the ratchet wheel and then rotate the drum and shaft, and means for automatically returning the drum to its normal position when uncoupled from the ratchet Wheel.

In testimony that I claim the foregoing as my own, I have'hereto affixed my signature in the presence of two Witnesses.

THOMAS S. CRAMPTON. lVitnesses HERBERT D. LAWSON, "AGNES RooKELLI. 

